In this paper, we report the design and implementation of a sound source separation system using a dynamically reconfigurable device. A robot in real-world environments should have an ability to treat a mixture of multiple sound signals. Active Direction-Pass Filter (ADPF) which extracts sound from a specific direction by using a pair of microphones has been developed as such a method of sound source separation. The ADPF was used as a front-end for an automatic speech recognition system, and recognition of three simultaneous speech signals has been reported. The ADPF, however, requires a lot of computational power, while the battery capacity and the physical size of the robot are limited. To reduce the power consumption and the size of the system, we adopted the dynamically reconfigurable device, "DRP" developed by NEC Electronics. We implemented the ADPF on DRP, and investigated the effectiveness of dynamically reconfigurable device for these applications. The preliminary experiment shows that ADPF on DRP separates a mixture of sound sources in real-time with practical accuracy.